Also:
"...The target launch cost is $1 million. As currently designed, Aquarius will be a single-stage vehicle 43 meters (141 feet) high and 4 meters (13.1 feet) in diameter and powered by a single engine using liquid hydrogen and oxygen propellants. The vehicle is floated in the ocean prior to launch to minimize launch infrastructure and will be able to place a 1,000-kilogram (2,200-pound) payload into a 200-kilometer (125-mile), 52-degree orbit...."
http://en.wikipedia.org/wiki/Aquarius_Launch_Vehicle

Of course they focused on ISS. But this would work better if launched from equator to zero inclination orbit. Plus launch it from a pipelauncher- you could probably double it's payload.
It's got a interesting way of getting the rocket vertical. You could use similar way to put rockets on a Pipelauncher. Instead using a cable and ballast, a pipelaucher could have a hinge- the pipelauncher would simply submerge until rocket became vertical, then have some way locking it into place.